Developing apparatus



March 10, 1931. A. LANGSNER DEVELOPING APPARATUS Filed Sept. 8, 1928 v 2Sheets-Sheet l March 10, 1931.

A. LANGSNER 1,795,724

DEVELOPING APPARATUS Filed Sept. s, 1928 2 Sheets- Sheet 2 \i.\.|lm|

[NVENTOR/ AO0LPH LHNGSNER,

W0 Y 74 ATn a Patented Mar. 10, 1931 UNITED. STATES I PATENT OFFICEADOLPH LANGSNER, OF CHICAGO, ILLINOIS, ASSIGNOB 'I'O EUGENE DIE'IZGENOOH PANY, OF CHICAGO, ILLINOIS, A CORPORATION OF DELAWARE 4 APPARATUSApplication filed September 8, 1928. Serial No- 304,773.

My invention relates to developing apparatus for light sensitivematerial and particularly to apparatus for developin light sensitivesheets or continuous strips paper 5 or the like by the action of a gas,such as ammonia or water vapor, or any other developing gaseous agent. i

One of the objects of my present invention is to provide a compact andconveniently operated apparatus for developing sheets or continuousstrips of light sensitive material by the action of a developing gaseousmedium contained within the apparatus, wherein the arrangement is suchthat a single operator standing at one point with respect to theapparatus is enabled to feed into'the machine either sheets orcontinuous strips of the material and is enabled to receive thedeveloped sheets or strips as they pass through the machine arid aredischarged therefrom, the construction being such that the developingmedium within the cabinet is prevented from escaping either through theinlet or the developing gases from reaching the operator.

Another object of my invention is to provide a compact and convenientlyarranged apparatus for developing sheets or continu-' ous strips oflight sensitive material by the action of developing gas enclosed withinthe' apparatus wherein the cabinet is constructed of such convenientheight so that it may be provided with an infeedingaperture forpermitting an operator to feed the light sensitive l material into themachine .on one point and wherein the cabinet is provided with adischarge aperture or station located at the top of the cabinet whichlatter station is substantially head high with the top of the operatorwhen located in operating position with respect to the cabinet andwherein an exhaustv dome or suction conduit is disposed imme diatelyadjacent and over the discharge station so as to pull or draw away theoccluded gases which are discharged with the developed paper at thedischarge station, the location of the discharge station being at headheight of the operator which provides for the upward rise of theoccluded gases into outlet of the apparatus thereby preventing e sldesin the provision of at non-corrosive into other paths.

the exhauster without coming into contact with the operator so that heis is not compelled to breathe in these escaping gases.

Yet another object of my invention resides in providing a developingapparatus ofthe character above described wherein the material to bedeveloped is passed continuously through the machine in the shortestpracticable route, and in a minimum of time for its complete developmentand is deliverable at the same side of the machine into which it wasfed, whereby a single operator can take care of both the infeed andoutfeed of the material.

Still another object of my invention resides in the particulararrangement of the driving means or specifically the driving beltswithin the apparatus for feeding the light sensitive material thereinto,therethrough, and therefrom, and in the relation of the means forpreventing the escape of the developing gaseous medium through theinfeed and outfeed ports of the apparatus.

Yet another ob ect of my invention relining for the developing apparatuswhereby the developing gases, such as ammonia gas, are completelyisolated from the Wooden cabinet which forms the developing apparatus.An ancillary object of this feature of my invention resides in the meansfor interconnecting the sheets of metallic lining material whereby toprevent the assage of the gases by or past the joints ormed in thelining material.

Yet another object of my invention resides in the general and particulararrangement of strips for the belt feeding rolls for the light sensitivematerial which are located at the outlet ports whereby the lightsensitive material, as it passes through the discharge port, is required(to pass between the rolls and is prevented from being diverted Stillanother feature of my invention resides in the provision of a dischargeroll receiving troughlocated opposite the discharge port and theprovision of a hood immediately ithereover for carrying the occludedgases which areon the discharged end of the developed paper whereby topre vent their disseminance into the atmosphere. An ancillary object ofthis feature of my invention resides in the modified constructionwhereby the exhauster is connected directly to an isolated compartmentformed at the.

discharge aperture whereby to draw away the occluded gases from thedeveloped paper as it passes through the discharge port.

Another object of my invention resides in the provision of the drivingmeans for regu lating the speed of movement of the small belts or cordsconstituting the feeding means for the light sensitive material.

These and other objects of my invention will be apparent from a perusalof the following specification when taken in connection with theaccompanying drawings, wherein:

Figure 1 is a side sectional view of my improved apparatus; v

Figure 2 is a front view thereof;

Figure 3 is a detail sectional view of the discharge opening showing thestripping members in position;

Figure at is a top plan view of Figure 3;

Figure 5 is a modified construction of the discharge opening; and

Figure 6 is a modification of the structure shown in Figure 5.

Referring now to the drawings in detail, my improved invention consistsof a selfcontained or practically air-tight or gas-tight cabinet adaptedto contain a quantity of developing material in a gaseous state. Thisdeveloping material may be either steam,

water vapor ammonia gas, or a combination of ammonia gas and water vaporor in fact any other gaseous medium for the development of the lightsensitive material. In the,

present instance, the specific embodiment of the invention isillustrated as adapted to conmonia or ammonia fumes. The lining or sheetwas tain a quantity of ammonia gas. As shown in the drawing, the cabinetis supported on suitable legs 2 so that the top of the cabinet stands ata suitable height which is inconvenient reach to an operator and sothat-the flat top of the cabinet may be utilized as a desk, table, orthe like. The cabinet is formed with preferably wood top, bottom, sideand end members and is preferably of rectangular form.

One of the particular features'of my invention resides in providing thecabinet with an inner lining of a suitable material which is noteffected by the corrosive action of the developing'gas, particularlywhen ammonial gas is used as a source of developing medium. In thepreferred form, my cabinet is formed of wooden members but likewise maybe formed of sheet metal or any other material. So also in the presentinstance, the cabinet is preferably lined with sheetmetal such as sheetlead or aluminum which is not affected by ammetal 6 as applied to theinner faces of the wooden cabinet members is formed in a sort of aflexible manner so that the junctions of the angularly disposed membersof the cabinet will make closed contact in order that the gases or steamnot only cannot escape but also cannot contact with the wood and injureit. In other words, my improved lining construction has a two-foldfunction: first, to prevent the contact of the injurious gases or steamwith the wooden or other members of the cabinet; and secondly, thejointsare so arranged and gasketed so as to prevent the escape of the gasesand steam past the joints.

To this end, the joints of the metal lining are preferably formed asshown in Figure 3 of the drawings wherein one of the sheet liners 6 isjoined to. another of the sheet liners 8 in such a manner to precludecontact of the gas with the wood. In this construction one of thepartition members 4 is grooved or recessed and this-groove is filledwith a yieldable gasket 10 of rubber or other suitable non-corrosivematerial which groove or recess extends the entire width or length ofthe particular cabinet member and the lining member lies in this grooveand then the yieldable rubber gasket overlies the portion of the liningmembers which lies in the recess. The area of the rubber gasket islarger than the area of the groove so that when the rubber is laid inthe groove a portion of it will project-beyond the face of the cabinetmem: her and its "lining and will firmly press against the oppositelined face of the cooperating cabinet member and since this yieldablejunction extends throughout the length of the two contacting cabinetmembers the flexible joint thus formed will compenmember to form a.gas-tight joint. In this manner of making a joint, for a developingchamber of the character indicated, the steam or gas and water vapor andparticularly ammonia gas will not have direct access to the Wood of thecase since if it did have such access the wood would warp and the poresof the wooden parts would absorb the moisture and crack, therebypermitting the escape of the obnoxious gases to the atmosphere outsideof the cabinet.

The foregoing construction readily lends itself to developing cabinetsmade of metal 'since the grooves may be formed directly in the metal andthe rubber gaskets inserted directly in these formed recesses.

In my present invention I have particularly formed my improved cabinetso that a single operator stan ing at a predetermined station withrelation to one part of the machine may easily take care of the machine,feeding in the continuous strips, or separate sheets if desired, oflight sensitive material, and receiving the developed sheet from the Idischarge point of the machine after the material has passed through thedeveloping chamber. To accomplish thisend, I provide a constructionwherein the light sensitive material is'preferably fed into the machineat the front or one of the sides of the same and is thence fed throughthe cabinet which contains the developing gas in the shortest possiblepath which will produce the desired developing effect and the materialis then automatically discharged at the outfeed station of the cabinetwhich is located at the same zone or station at which the infeed islocated. In the particular embodiment illustrated, I provide the frontof the machine preferably at the lower portion thereof with atransversely extending infeed opening or slot 12 for receiving the lightsensitive material to be developed. Opposite this slot, I provide theexterior of the machine with a shelf or support 14 on the under side ofwhich depends a bracket 16 carrying a roller 18 for holding a continuousroll or sheet of light sensitive material 20. In lieu of this, separatesheets of light sensitive material may be placed on the shelf or feedingthrough the slot 12, if desired. Opposite the slot 12, I provide asingle compartment 22 formed by a vertically disposed partition 24 and ahoriontally disposed partition 26 which partition extends across thefront of the machine co-extensive with its width. Inside of thiscompartment 22 I provide two spaced apart rollers 28 and 30 which areprovided with a series of spaced apart grooves for receiving a pluralityof relatively small belts or cords 32 and 34. I also provide a guidingledge 36 which lies flush with the upper surface of the shelf 14 andprojects inwardly to the bight of the rolls so that the inner end ofthis guide 36 overlies the lower roll 28. I also provide a rubber, felt,or partition of other material 38 which extends from the front wall 4 ofthe cabinet to the roll 30. Partition 24 is provided with an opening 40for the passage of the belts or cords 34 and with rubber or felt gaskets42 which permit the passage of the cords or belts but prevent the escapeof the gases through the opening 40. In a similar manner, the horizontalpartition 26 is provided with two openings 44 and ,46 for the'passage ofthe belts and cords which pass around the roller 30. These openings 42and 46 are likewise provided with felt or rubber gasket strips.

About midway the height of the cabinet and located at the rear or on theother side of the cabinet, I provide a drum 'or roll 48 and is providedwith a pulley 52 having variant diameters and forming one member of achange speed gearing. A belt 54 runs over this pulley and is adapted tobe driven by another smaller pulley 56 mounted on a shaft 58 carrying aworm wheel 60 meshing with a worm 62 on a shaft 64 and an electric motor66 in turn mounted on a bracket 68 on the exterior of the cabinet; Inthis manner, I provide a simple, direct driving means of variant speedtransmission between the motor and the relatively large roll or drum 52.In addition, I provide a rear portion of the cabinet with a plurality ofguide rolls 7 0, 72, 74 and I provide the front upper portion of themachine with another pair of guide rolls 76 and 78. These two latterrolls are mounted directly opposite the discharge opening or slot 80located in the front panel of the developing cabinet.

The two sets of endless cords or belts 32 and 34 cooperate with thesevarious rollers and with the openings in the partition mem-' bers andcabinet members so as to feed either continuous sheets or separatesheets of light sensitive material directly through the cabinet in aminimum of time during which time the sheets are subjected to the actionof the developing gas or medium so as to cause the development of thelight sensitive material. Referring now to the lower belts or sets ofcords 34, it will be seen that the same-pass around the roller 28,thence relatively upwardly and around the upper roll 30, thence throughthe-guide slot 44, thence around a separate roller 82, thence across andat an inclined manner upwardly to the rear of the machine hence theypass around the relative- 1y large developing drum 48 and thenceforwardly and still upwardly to the front of the machine where they passaround the upper guide roll 76, thence rearwardly around the roll 72,thence downwardly around the roll 70, thence forwardly and downwardlyand through the slot 40 in the partition 24, thence around roll 28against, completing a continuous circuit. In a similar manner, the beltsor cords 32 pass around the guide roll 30, thence upwardly through theslot 44 and partition 26, thence around roll 82 and rearwardly andupwardly together with the cords 34 around the developing drum 48,thence forwardly around the front and upper guide roll 78, thencedownwardly directly through the slots 46 in the partition 26 to theguide roll 30, again also completing a continuous circuit. It will benoted that the two belts travel together from the lower guide rolls 28and 30 1 distinct grooves in the various rolls, any light sensitivematerial in sheets or continuous strip form that is fed onto the shelf14 and onto the guide ledge 36 and projectedinto the plane of the beltsopposite the opening 12- such material will be carried by the opposedbelts through the relatively short path upwardly aroundthe roll 82,thence upwardly in an inclined direction to the rear of the ma chinearound drum 48, thence forwardly and discharged by the discharge rollers7 6 and 7 8,

preferably as shown in Figure 1, into. a receiving trough 84 whichreceiving trough is located immediately beneath the exhausting hood 86which is adapted to remove any occluded gases which may be in thedeveloped material orwhich may possibly escape through the dischargeopening. It will be understood that this hood extends the entire Widthof the front and lies immediately over the receiving trough 84.

The tension on the belts is preserved by means of the tension roller 7 4which runs on roller bearings'and is carried by arms 86.

which in turn are pivoted upon plates 88 so as to takev up the slack inthe strings. In

, other words, the weight of the ball bearing rollers 74 pivotally andfreely lying on the two pairs of cords or belts 32 and 34- automaticallytakes up the slack in these cords While still permitting the freepassage of the light sensitive paper therebetween as it passes throughthe short quick route through the developing chamber. It will beobserved that by providing the front and re'ar'surfaoes 88 and 90 of thecabinet asglass partitions, the

progress of the .developing may be observed at all times and if desired,these-panels may be made hinged and detachable so as to give free accessto the inner portions of the developing chamber.

In order to provide a suitable source of developing medium, I provide atthe base of the machine, spaced apart guides 92 which are in the form ofshelves adapted to sup port developing pans or trays 94 and 96 adaptedto contain suitable developing solution such as water or liquid ammoniawhich is heated in any suitable manner as for-instance by means of anelectric heater, if desired. These pans are preferably filled from theexterior of the cabinet by means of suitable flexible hoses or pipeswhich have filling nozzles on the outside of the cabinet wall.

Means is providedat the (lISCllflIgQll'lOllth.

bf the cabinet for stripping the sheets or continuous strips of lightsensitive material from the cords and preventing them from following thecords as the cords pass around the rolls. This construction isillustrated clearly in Figures 3 and 4 of the drawings wherein I providea pair of preferably sheet metal prongs or stripping fingers which arepreferably fastened to the under sides of the slot in the front panel 4.These stripping fingers 98 and 100 have their inner portions formed astongues 102 so as to lie in relatively wide peripheral grooves 104formed in the rollers 7 6 and 78. These grooves alternate with thegrooves 106 into which. the cords or belts 32 and 34 lie. In addition, Iprovidea flexible gasket of felt or rubber shown at 108 in Figure 3 ofthe drawings, which is held in place by means of a block 110. Thisfinger lies across the discharge slot 80 in a manner so as to permit theoutfeed of the developed material while preventing the escape of the gastherethrough.

As an alternative construction to that shown in Figures 1 and 3 of thedrawings, I provide the modified construction of the upper frontportion, shown in Figure 5, whereat an isolated discharge chamber isformed by means of a horizontal partition 112 and a vertical partition114, which partitions with the front and upper walls 4 of the cabinetprovide an isolated chamber, one wall of which is provided with aplurality of perforations 116 which connect with an exhauster forsucking the air out of the compartment 118. In this compartment, I mountthe rolls 120 and 122 which likewise are grooved and around which thebelts 32 and 34 are adapted to pass. The partition 114 is provided withslots .123 for the passage of the belts while the partition 112 islikewise provided with a slot 124 for the passage. of the lower cord orbelt 32. These openings are suitably packed or gasketed with felt orrubher as hereinbefore described so that the chamber 118 issubstantially isolated from the developing chamber.. In like manner,this 420*.

chamber 118 is provided with a discharge slot 126 and is provided withstripping fingers 128 and 130 as hereinbefore described, and in additionis provided with a flexible gasket .132 and a shelf 134 so that lightsensitive material carried by the belts will pass through the opening120 between the discharge rolls 7 120 and 122. From this point, the.light sensitive material is fed out thr ugh the discharge-slot 126 pastthe yieldabl gasket 132.

Since this chamber v118 js completely cut of from the developingchamber, the light sensitive material discharged may be discharged ingtogether pass through a slot 148 so that the light sensitive materialcarried thereby is discharged from between the rolls 136 and 138 intothe separate chamber 150 which as shown is closedand the paper is thendischarged into this chamber in the form of separate sheets or acontinuous roll 160. The

front wall 162 of this chamber is formed at a door hinged at 164 so thatin an open position, it moves to a downward dotted-line position to forma shelf. When closed, this door 162 forms a closed chamber 150 which isat all times connected with an exhauster 144 so that the light sensitivematerial fed into this compartment is at all times under the suction ofthe exhauster so that the occluded gases remaining on the paper will Ibe withdrawn therefrom. In like manner,

any gas which may escape from the developing chamber through the slot148 is likewise taken care of. It will be understood that the partitions140 and 142 are provided with a sufiicient number of slots for thepassage of belts therethrough as hereinbefore described and alsoprovided with felt gaskets and packed as hereinbefore described.

It will thus be seen that l have provided a very simple, compact,eficient and economical type of developing cabinet which may he caredfor by a single operator and wherein the developed material such forinstance as paper, is passed through the machine in the shortestpossible route so as to give the maximum time for developing while atthe same time during the passage, material is carried by the spacedapart open strands of the belts or cords in a path directly over therising developing gaseous medium upon the pans. It is automaticallydischarged without the interposition of the operator. All

the operator has to do is to feed in the material at the front basalportion of the machine and to receive it at the upper front portion ofthe machine, which stations are all within 'his reach. It will also beseen that the drive is accomplished by driving the relativelylarge drum48 so as to drive the two separate sets of belts or strings. This drivemay be suitably controlled by varying the ratio of the driving pulleys.will, of

course, be understood that wherever the shaft of the driving pulleyprojects from the easing the same is provided with suitable packing orgaskets to prevent the escape of the gases.

It will also be apparent that by reason of constructing my improveddeveloping cabinet so that the top is substantially the height of thehead of the standing operator, the top of the cabinet may be used as asupport or shelf for various articles while at the same time thelocation of the discharge station or aperture at the top of the cabinetsubstantially at head height of the operator permits the discharge ofoccluded gases at this height from the ground so that in discharging,they will rise and pass above the head of the op erator directly intothe suction exhauster thereby preventing the injurious effects of thegases reaching the operator.

Another factor of the construction illustrated resides in disposing thisdischarge aperture at the same side of the cabinet as the'infeed stationwhereby a single operator at this point may take care of both the infeedand the outfeed of the single develop-ing machine.

In connection with the feature of my in vention illustrated more clearlyin Figure 3 of the drawings, which shows the non-corrosiv'e linercovering for the inner surface of the wood of the cabinet, it is ofcourse to be understood that this thin non-corrosive lining member maybe made of any material such as aluminum, Monel, lead or any othernon-corrosive metal or may be made of a non-metallic material. In someinstances, I may also provide the inner lining of noncorrosive materialcomposed of celluloid or any other similar plastic material or metal. Imay also spray the inner face of the wood of the cabinet withnon-corrosive substances which will provide a thickness approximately asthick as lead or aluminum sheets, for

protecting the wood against the action of the ammonia gas or vapor orsteam or other gas. In some instances, 1 may use celluloid, casein orany other similar substance whlch will cover the entire surface andstick or adhere to the wood. In connection with the formation oi: thegrooves in the wooden partition members of the cabinet, it will bepointed out that they'hold the rubber or bther yieldable packing inplace and afi'ord means for sealing the joints irrespective of whetherthe yieldable packingis positioned on a flat board or frame or whetherit is inserted onthe edge. So also, itawill be apparent that by carryingthe metal lining or covering V 7 through into the grooves and over thesurv face of the border casing with which the rubber comes in contactprovides a further protection to any portion of the wood against theattack of the ammonia, the ammoma fumes, or steam or vapor. Rubber 15particularly adaptable for this function since it is not influenced orchanged by aonia or by any acid used in the developing work.

Having thus described my invention, what I claim as new and desire tosecure by Letters Patent is: v i

l. A developing apparatus of the characterindicated comprising membersformingan enclosing cabinet, the top of which is relatively low so as toform a flat table-like sur-' face, one wall of the cabinet having aninlet slot for the infeed of light sensitive material and having adischarge opening located at a point on such wall so that a singleoperator without moving may feed light sensitive material into the inletand receivethe same in fully developed conditionirom'the'dischargeopening, a plurality of guide rolls within said cabinet, means forrotating certain of said rolls','and a plurality of sets of conveyorsdisposed around said rolls in endless paths, certain of said rollscomprising a pair lying opposite the infeed slot and certain of saidrolls comprising a separate pair lying v weaverterial from an inletopening of said cabinet to a discharge opening of the cabinet, a sourceof ammonia gas in said cabinet, and means for preventing the dischargeof the ammonia gas through said inlet or outlet opening.

4. In a device of the class described, the combination of means formingan enclosing cabinet, the upper surface of which is fiat and relativelylow so as to provide a table surrace, one wall of said cabinet having atits lower portion an opening co-extensive with the width of said wall toprovide an infeed slot, a pair of guide rolls opposite the infeed slot,the upper portion of said front wall having an outlet opening, a pair ofguide rolls opposite said outlet opening and a relatively largedeveloping drum located intermediate the height of the cabinet and adiacent the rear wall of the cabinet, and a plurality of sets of endlessconveyors lying in peripheral grooves in said rollsand around saiddeveloping drum, said conveyors and rollers being opposite the dischargeslot, said conveyors and rolls being arranged so as to carry the lightsensitive material introduced at the inlet slot across the chamber andthence back again to the outlet slot in a continuous path, means in saidcabinet for subjectin the traveling light sensitive material carried bythe belts to the action or a gaseous developing medium and a lining forthe'inner surfaces of the cabinet walls, said lining comprising a thinsheet of inert material which is not affected by the action of thegaseolls developing medium. v

2. A developingapparatus of the character described comprising woodenmembers forming an enclosing cabinet, said membe s belng lined withsheet material which is n t affected by the action of ammonia gas, sai

lining materials at their junctions being provided with gas-proofjoints, an infe'e'd open ing for said cabinet and a discharge openingfor said cabinet and conveying means in said cabinet constructed andarranged to continuously transport light'sensitive material from a theinlet opening to the outlet opening and a source of ammonia gas in saidcabinet for causing the development of the light sensitive v materialduring its passage therethrough. 3. In a device of the class described,the combination of wooden members forming an enclosing developingcabinet, said members being provided with an inert lining which is nota'flected by the action of ammonia gas,

certain of the wooden members being provided with grooves into which thelining extends, the said grooves being provided with I resilient gasketswhich are larger than the I dimensions of the grooves, whereby saidgaskets are pressed against the lining in the grooves to provide agas-tight joint, means in said cabinet for passing lightsensitivemaconstructed and arranged whereby light sensitive material fed betweenthe pair of rolls opposite the infeed slot is conducted between saidbelts to the rear of the mabhine and around said developing drum, andthen forwardly to the front of the machine and discharged through saiddischarge opening,

means forming a source of developing gas in said chamber for acting uponthe light sensitive material as it is carried along by the belts andmeans for preventing the escape of said gas through the inlet or outletopenon the inside of the cabinet, a relatively large developing drumdisposedat the rear of the cabinet substantially mid-way its height anda plurality of other guide rolls disposed in said cabinet, a pluralityof endless conveyors lying in peripheral grooves passing around saiddeveloping drum, means providing a source of developing gas lying insaid developing chamber' and underlying the course or pathway of theconveyors asthey pass together from the iufeed slot to the dischargeslot, and means for preventing the passage oif'the gases through theinfeed and discharge s'ots.

6. In a device of the class described, the combination of means forminga developing cabinet provide with an infeed slot for the introduction ofight sensitive material into the cabinet, a relatively large developingdrum disposed adjacent its rear wall and substantially mid-Way itsheight, said drum having a shaft projecting through the exterior Wall ofthe cabinet, a bracket adjacent said exterior projecting shaft, anelectric motor on said bracket, a variable speed driving connection fromthe end of said motor to the shaft, a plurality of guide rolls in saidcabinet, certain of said rolls providing a pair of rolls opposite theinfeed slot, in the wall of the cabinet, certain of said rolls providinga pair of rolls opposite the discharge opening formed at-the wallsof thecabinet, a plurality of sets of endless conveyors passing around saidpair of rolls and said developing drum, and arranged so that saidconveyors travel together from said pair of rolls'around said developingdrum to the other pair of rolls, means in said cabinet providing asource of developing gas, and means for driving said conveyors by therotation of said developing drum.

7. In a device of-the class described, the combination of means forminga developing cabinet having an infeed slot at the front lower portionthereof and having a discharge opening at the upper portion thereof, anexhauster located adjacent saidldischarge station so as to withdraw thegases at such point, and feeding means containedwithin said cabinet andadapted tofeed light sensitive material inserted through said infeedslot and convey it through said cabinet and discharge the same at saiddischarge slot, a source of developing gas within said cabingt adaptedto develop light sensitive material during its passage and a liningforthe inner surfaces of the cabinet walls, said lining comprisinga thinsheet of inert material which is not afiected by the actionof thedeveloping gas. w

8. lln a device of the class described, tlie combination of meansforming a developing cabinet provided with an infeed slot and a Idischarge opening, a pair of rollers located at the infeed slot and atthe discharge opening, said rollers having spaced apart peripheralgrooves, a plurality of other guide rolls in-.

:luding a substantially large developing drum located insaid cabinet,aplurality of sets of endless cords passing around said rolls and saiddeveloping drum, and lying in said peripheral grooves whereby to providelight sensitive material feeding means and stripping fingers adapted tolie in peripheral grooves in the pair of discharge rolls, said strippingfingers being constructed and arranged to compel the discharge of thelight sensitive materialoutwardly between said discharge rolls.

9. In a device of the class described, the combination of means forminga developing cabinet provided with an infeed station and an outfeedstation, apair of rollers located at each station around which pass aplurality of endless conveyors which lie in peripheral grooves in saidrolls, said rolls opposite the discharge station having a plurality ofrelatively Wide grooves alternating with the cord grooves and flexiblefingers mounted so as to lie in said grooves, and acting as strippingmembers for directing the light sensitive material outwardly throughsaid rolls to the discharge station.

10. A developing apparatus for developing light sensitive material bythe action of a gaseous developing medium comprised of Wood membersforming an enclosing cabinet, a source of gaseous developing medium insaid cabinet, means for introducing light sensitive material into saidcabinet to be de- 7 Veloped therein, the inner walls of said wood beingfaced with a lining of thin inert material of a character not affectedby the action of ammonia gas.

11. A developing apparatus'for developing light sensitive material bythe action of 12. A developing apparatus for developing light sensitivematerial by the action of a gaseous developing medium, said cabinetbeing formed of joined together members, the inner walls of which arelined with a mate-v rial not affected by the corrosive action of thedeveloping gas within the cabinet, one of the adjacent joined togetherwalls having a superficial recess therein, the inner lining of said walllying in said recess and a. flexible gasket of non-corrosive materiallying in said recess and beingiof larger area than said recess wherebyto project beyond said recess and press firmly against the opposite wallof the other joint member whereby to prevent passage of gas past saidjoint.

13. A developing apparaius for light sensian atmosphere of a developingmedium within the cabinet, an impervious sheathing covering the innersurfaces of the cabinet walls, means comprising a compressed strip ofresilient material of circular cross section arranged in grooves ofsmalldimension formed in the abutting edges of the cabinet Walls at the seamsthereof whereby to prevent the escape of the developing medium throughthe seams.

15. A developing apparatus for light sensitive material comprising acabinet having an opening for the insertion of light sensitive materialinto the cabinet, means for creating an atmosphere of a developingmedium Within the cabinet, means comprising an impervious sheathingformed and arranged to the inner walls of the cabinet for preventing thedeveloping medium from penetrating the cabinet Walls and thus escapinginto the atmosphere surrounding the cabinet, said cabinet having groovesformed in the abutting edges of its side walls and a gasket of resilientmaterial compressed into said grooves, the edges of the impervioussheathing extending across and into said grooves.

16. A developing apparatus for light sensitive material comprising acabinet provided a with an aperture for the insertion of light sensitivematerial into the cabinet, means for'creating an atmosphere of adeveloping medium within the cabinet and means comprising a compressedgasket of resilient mabeing lined with sheet material which is notafiected by the action of ammonia gas, said lining materials at theirjunctions being pro vided with gas-prooi joints, an infeed openingforsaid cabinet and a discharge opening for said cabinet and conveyingmeans in said cabinet constructed and arranged. to continuouslytransport light sensitive material from the inlet opening to the outletopening and a source of ammonia gas in said cabinet for causingthe'development of the light sensitive material during its passagetherethrough, and means at the outlet opening for removing from thelight sensitive material any ammonia fumes occluded therein during thepassage of the material through the developing chamber.

lln Witness whereof, I have hereunto subscribed my name.

ADQLPH LANGSNER.

terial arranged in the seams of the cabinet whereby to prevent theescape of the develope inggas therethrough and means comprising animpervious sheathing formed and arranged'tothe inner walls of thecabinet for preventing the developing medium from penetrating thecabinet walls and thus escaping into the atmosphere surrounding thecabinet.

17. A developing apparatus for light sensitive material comprising acabinet provided with an aperture for the insertion of light sensitivematerial into the cabinet, means fpr creating anatmosphere of adeveloping medium within the cabinet, means comprising a compressedstrip of resilient material of circular cross section arranged ingrooves of smaller dimension formed in the abutting edges of the cabinetwalls at the seams thereof whereby to prevent the escape of thedeveloping medium through the seams and and into said triangular groovesbeneath the rubber gasket.

18. A developing apparatus of the character described comprising woodenmembers forming an enclosing cabinet, said members means comprising animpervioussheathing formed and arranged to the inner Walls of thecabinet for preventing the developing medium from penetrating thecabinet walls and thus escaping into the atmosphere'surrounding thecabinet, said sheathing extending around the edges of the walls of thecabinet y no

